Baez is held hostage in an interrogation room by a distressed man who wants to see his daughter. Elsewhere, Garrett's son gets in trouble with the law, so Garrett turns to Frank for help, creating an ethical dilemma for the police commissioner.

Baez is held hostage in an interrogation room by a distressed man who wants to see his daughter. Elsewhere, Garrett's son gets in trouble with the law, so Garrett turns to Frank for help, creating an ethical dilemma for the police commissioner.

A woman's body is discovered ritually posed, and odd symbols turn up in her apartment. Soon, a monk becomes the prime murder suspect, and Castle thinks there is a conspiracy at work. Meanwhile, Castle struggles to accept Alexis' new living arrangements.